Jet is a type of lignite, a fossilized driftwood which dates to the Toarcian age of the early Jurassic, some 180 million years ago.

The deposits recovered from Whitby are generally acknowledged as being the finest in the world and it was popularised as a gem material when used in mourning jewellery by Queen Victoria.

This pure black specimen displays a wavy, ridged surface texture and is blemish-free despite having a hardness of just  between 2.5 and 4 on Moh's scale.

weight:  21.28 carats
shape:   Part-polished natural specimen
dimensions:  25.45 x 24.12 x 12.01 mm
treatment:  None